MORPHOLOGICAL CHANGES IN Portulaca oleracea L. UNDER SALT STRESS

Abstract

ABSTRACT:Halophyte plants are known to tolerate environments with high salt concentrations, although there are intraspecific differences in the level of tolerance borne by these plants. Portulaca oleracea L., commonly known as Purslane, is mentioned in the literature as a halophyte species that shows tolerance to salinity, but this tolerance is genotype-dependent.The present study aimed to evaluate if a Purslane access (B1) is highly tolerant to salinity, to be used in future studies on the mechanism(s) promoting this tolerance. For that, morphological changes the B1 access were evaluated once submitting it to saline stress at concentrations of 0.0; 0.2; 0.4; 0.6; 0.8; 1.0; 1,2; 1.4; 1.6; 1.8 and 2.0 g of NaCl / 100 g of substrate. Seeds were germinated in culture medium (MS ½ strength, Phytagel 0.2%, and pH 5.8) and then transferred to 200 mL plastic cups with 100 g of substrate. After 35 days, saline solutions containing different amounts of salts were added to the substrate in order to subject the plants to the different levels of salts above mentioned. The experiment was conducted in a plant growth chamber in which temperature was set at 25 ±2°C, 65 ±5% of air relative humidity and 500±20 μmol/m -2 /s -1 of PAR, and a photoperiod of 16/8 h (light/dark). The most common morphological characteristics (shoot growth, leaf area and number, stem succulence, leaf color and stem color ) were monitored for a period of up to 12 days, after the onset of saline stress.The experimental design was completely randomized with three replicates per treatment.Purslane plants showed practically no changes in the variables evaluated up to 1.2 g of salt.Even in the highest concentrations, the plants remained alive. KEYWORDS:Abiotic stress, salt tolerance, Purslane. ALTERAÇÕES MORFOLÓGICAS EM PALAVRAS-CHAVE:Estresse abiótico, tolerância à salinidade, Beldroega.

Nutritional Composition, Bioactive Compounds, and Volatiles Profile Characterization of Two Edible Undervalued Plants: Portulaca oleracea L. and Porophyllum ruderale (Jacq.) Cass

“…The absence of strong relationships between Zn ( P. oleracea ), K, and Na ( P. ruderale ) may be due to species-specific biosynthesis/transport processes that are influenced by geoclimatic conditions during growth depending on the harvest period, as suggested by [ 58 , 66 ]. The complete relationship between Na and P ( P. oleracea ) can be explained by the fact that the studied species are halophyte plants [ 67 ]. The correlations of different degrees found between compounds in both plants were weak, especially for total chlorophyll ( P. oleracea ).…”